One capped rivet according to the present invention comprises a cap having an exposed upper surface and a lower surface, and a rivet having a rivet shaft extending in a direction away from the lower surface of the cap, a rivet flange extending in a horizontal direction away from an axis of the rivet shaft for fixedly attaching the rivet to the cap, and a pair of support portions disposed between the rivet shaft and the cap, extending substantially parallel to the lower surface of the cap, and formed by making a pair of apertures in the rivet flange and bending two portions of the rivet flange along bending lines respectively extending between the apertures and the rivet shaft.
A capped rivet of this type is used, for example, for attaching a snap button, an ornamental or the like to a woven material to be supported such as a garment or a bag. For attachment, a rivet shaft is pierced through the supporting material and then deformed so as to attach the capped rivet fixedly to the supporting material. For protection of the supporting material and fastening of a snap button, firstly an eyelet or a spherical counterpart is brought up on the rivet shaft which has been pierced through the supporting material and then can be pressed against the supporting material by deformation of the rivet shaft. The deformation of the rivet shaft is generally done by using an attaching machine equipped with an attaching implement which contacts an exposed upper surface of the cap and pierces the rivet shaft through the supporting material and press it against a member holding a counterpart.
An existing capped rivet of the above-mentioned type is shown in FIG. 4. A rivet 110 of this capped rivet has, in addition to a rivet shaft 112 and a rivet flange 114, two support portions 120 disposed between the rivet shaft 112 and a cap 100 and extending substantially parallel to a lower surface of the cap. These support portions 120 are formed by means of making two apertures 118 at the two respective portions of the rivet flange and bending the two portions of the rivet flange along bending lines respectively extending between the apertures 118 and the rivet shaft 112. In order to avoid a problem of marking an impression on an upper surface of the cap 100 by the attaching implement, the support portions 120 has support surfaces for preventing the cap 100 from escaping toward the rivet shaft 112 by action of the attaching implement. Further, in the case of the capped rivet shown in FIG. 4, in order to prevent the supporting material from possible puckering when it is attached, the vertical interval X of a pressure-contact section 116 on a lower surface of the rivet flange 114 and a lower surface of an inwardly curved edge 106 of the cap 100 is reduced. The capped rivet of this type is known by EP-A2-0 146 133.
However, in use of the capped rivet of the type shown in FIG. 4, if the cap is made using thinner material for reduction of the material cost, an impression would be marked on the upper surface of the cap by the attaching implement.
In view of the foregoing problems, a main object of this invention is to provide a capped rivet which can be prevented from an impression of an attaching implement on an exposed upper surface of the cap when it is attached to a material to be supported, even when the cap is made from thin material.
In order to achieve the above object, it is proposed that in the capped rivet of the above-mentioned type, the support portions should be bent in such a manner that one support portion covers the other, wherein a surface of one support portion that faces away from an inner surface of the cap at least partly contacts a surface of the other support portion that faces toward the inner face of the cap.
With such an arrangement of the support portions, the other support portion that contacts the surface of the one support portion that faces away from the inner face of the cap has an additional support surface for keeping the one support portion from being escapingly moved when it comes into contact with the cap escaping toward the rivet shaft by action of the attaching implement. This can prevent a problem of marking an impression on the cap by the attaching implement during attachment of the capped rivet, even when a cap which is thin in material is used.
For manufacturing a capped rived according to this invention, relatively large support portions need to be cut out from the rivet flange and bent whereby the corresponding large apertures of the rivet flange are formed. Therefore, in order to make the rivet flange stable in spite of such large apertures formed in the rivet flange, the bending lines preferably extend substantially in parallel on two confronting side surfaces of the rivet shaft in such a manner that large non-aperture areas of the rivet flange extending between the apertures of the rivet flange are formed between the bending lines for reliably obtaining a desired stability of the rivet. Further, it is especially preferable that the apertures are substantially laterally symmetrical with respect to a plane including an axis of the rivet flange.
The other support portion that contacts the surface of the one support portion that faces away from the inner face of the cap is at least partly placed on the rivet flange and/or an upper edge of the rivet shaft, so that the cap can be stabilized so as not to move toward the rivet shaft.
In order to fasten the rivet to the cap, an outer edge of the rivet flange is preferably supported by a downwardly and inwardly curved outer edge of the cap below.
A pressure-contact section of the rivet flange, against which the supporting material is pressed after it is pierced through by the rivet shaft and the rivet shaft is deformed, is in contact with the rivet shaft and extends substantially perpendicularly to an axis of the rivet shaft, and further, when the support portions are disposed between the pressure-contact section and the cap, a relatively large interval can be kept with respect to the cap though an impression is prevented.
With this arrangement, when the rivet flange has a transitional section extending from the pressure-contact section toward the cap and an outer edge section extending horizontally from the transitional section away from the axis of the rivet shaft, a vertical interval can be especially reduced between the pressure-contact section of a lower surface of the rivet flange and a lower surface of the downwardly and inwardly curved outer edge of the cap, in order to fasten the rivet to the cap.
The cap of the capped rivet according to this invention has preferably a substantially semi-spherical shape.
In case that a counter part such as a spherical or an eyelet-like snap button is to be fastened to a surface of the supporting material that confront with the cap, it is especially preferable that a support surface of the counterpart which faces toward the rivet flange confronts with the pressure-contact section of the rivet flange.